Root cause: fitToGraph's clampPan clamped against graphBoundsRef, which a separate effect populated from NORMALIZED bounds — on first paint the ref was still {0,0,0,0}, so pan clamped to +/-viewport (off-center) and only a manual drag re-ran clampPan against the committed bounds. Fit now runs on normalizedPositions (fit-space == render-space == clamp-space), after the setGraphBounds effect, deferred a double-rAF so the committed bounds are live before clampPan; ResizeObserver still drives the hidden->visible 0->N fit. Manual-layout opt-out preserved.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>